1. Field of the Invention
The present invention relates generally to methods for applying identification markings to tire appliques and, in particular, to a laser cutting method therefor.
2. Description of the Prior Art
Tire manufacturers provide a serial number on each tire for identification purposes. As a role, however, the manufacturer's identification number, which may actually be a combination of numbers and letters, is rather small in size and not positioned well for viewing when the tire is mounted on a vehicle.
There are often situations where having only the manufacturer's serial number on a tire is insufficient, such as because of the relative difficulty in reading this serial number at a distance or at a glance. For example, ear rental agencies must be vigilant to protect against customers switching tires on rental cars while the cars are in the Gustomar's possession off the premises of the rental agency. To prevent such an ocurrance, the rental agency needs to make a quick and accurate identification of the tires on the rental vehicles when they are returned to the agency by the customer. In such a situation, it is desirable to have a tire identification marking which is readily accessible to viewing, easy to read, attractive and not readily removable from the tire.
In U.S. Pat. No. 2,988,216 there is disclosed a tire applique and method of application which involved cutting a multi-layered applique in a configuration or configurations which produced by the margins of the cuts the identifying indicia. In this method, the cutting step created windows or apertures in the applique, making visible the tire wall which contrasted in color with the surface of the applique. Although not particularly described in detail in this patent, the cutting method employed involved a die cutting procedure.
Because the amount and types of identifying material which could be employed were limited by the die cutting procedure, there was developed an improved tire applique and method for making same which employed a hot stamping process to stamp a color contrasting material into depressions made in the applique by the stamping die. This method is fully disclosed in U.S. Pat. No. 4,256,159.
Although both of the above methods offer certain advantages in the manufacture of tire appliques, they both also suffer restrictions in the types of identifying indicia which may be employed on the applique. For example, neither of the methods disclosed in the above-described patents is particularly well suited to generate bar coding information, change fonts, indicia sizes, or consecutively number indicia on successive appliques without changing dies.
The following patents disclose various methods for manufacturing tire appliques:
______________________________________ U.S. Pat. No. Inventor ______________________________________ 1,544,262 Midgley 4,343,342 McDonald 4,684,420 Bryant et al. ______________________________________
The '262 patent to Midgley discloses a method for marking tires in contrasting colors without requiring the application of a pigment. The method involves heating the tire in contact with a band which overlaps the meeting edges of the tread and sidewalls and which is composes of a metal capable of chemically reacting with the tire material to produce a change of shade in the tire surface.
The '342 patent to McDonald discloses a tire having debossed or embossed identification markings which are generated on the tire during the molding or vulcanization process.
The '420 patent to Bryant et al. discloses a transfer decal process of applying identification markings on a vehicle tire. In this method, a polymeric paint or film is applied to selected portions of a release substrate to form a decal which is in turn placed into a tire mold. The mold is then closed and the polymeric paint is brought into contact with the tire.